These commissioners constitute the legislative body of the city and, as a group, are responsible for taxation, appropriations, ordinances, and other general functions. Individual commissioners are also assigned executive responsibility for a specific aspect of municipal affairs, such as public works, finance, or public safety. As such, this form of government blends legislative and executive branch functions in the same body.

One commissioner may be designated to function as chairman or mayor, but this largely is a procedural, honorific, or ceremonial designation and typically, does not involve additional powers beyond that exercised by the other commissioners. Chairing meetings is the principal role. Such a "mayor" is in many ways similar to the "weak mayor" form of mayor–council government, but without any direct election for the office.

This form of government originated in Galveston, Texas as a response to the Galveston Hurricane of 1900, mainly for the reason that extra support was needed in certain areas. After its constitutionality was tested and confirmed, this form of government quickly became popular across the state of Texas and spread to other parts of the United States.

Portland, Oregon remains the only large city in the United States that still has a city commission form of government.[2] A measure to change to the council-manager form of government was defeated 76%-24% on the May 2007 ballot.[3]

As a form, commission government once was common, but has largely been supplanted as many cities that once used it have since switched to the council-manager form of government. Proponents of the council-manager form typically consider the city commission form to be the predecessor of, not the alternative to, the council-manager form of government.[1] The council-manager form of government developed, at least in part, as a response to some perceived limitations of the commission form. In the council-manager form, the elected council exercises the legislative power of the city and appoints a manager, who possesses the executive power. Thus the executive powers, divided among the commissioners in a commission form, are instead concentrated in the manager, who then delegates responsibility to department heads and other staff members. The council-manager form became the preferred alternative for progressive reform, and after World War I, very few cities adopted the commission form and many cities using the commission plan switched to the council-manager form. Galveston itself changed forms in 1960.[1]